1. Field of the Invention
The present invention relates to electrical connectors and more particularly to modular jacks for use in telecommunications equipment.
2. Brief Description of Earlier Developments
Modular jacks are used in two broad categories of signal transmission: analog (voice) and digital (data) transmission. These categories can overlap somewhat since digital systems are used for voice transmission as well. Nevertheless, there is a significant difference in the amount of data transmitted by a system per second. A low speed system would ordinarily transmit from about 10 to 16 megabits per second (Mbps), while a high speed system should be able to handle 155 Mbps or even higher data transfer speeds. Often, high speed installations are based on asynchronous transfer mode transmission and utilize shielded and unshielded twisted pair cables.
With recent increases in the speed of data transmission, requirements have become important for electrical connectors, in particular, with regard to the reduction or elimination of crosstalk. Crosstalk is a phenomena in which a part of the electromagnetic energy transmitted through one of multiple conductors in a connector causes electrical currents in the other conductors.
Another problem is common mode electromagnetic interference or noise. Such common mode interference is often most severe in conductors of the same length, when a parasitic signal induced by ESD, lightning or simultaneous switching of semiconductor gates arrives in an adjacent electrical node through multiple conductors at the same time.
Another factor which must be considered is that the telecommunications industry has reached a high degree of standardization in modular jack design. Outlines and contact areas are essentially fixed and have to be interchangeable with other designs. It is, therefore, important that any novel modular jack allow with only minor modification, the use of conventional parts or tooling in its production.
There is, therefore, a need for a modular jack which will reduce or eliminate crosstalk in telecommunications equipment.
There is also a need for a modular jack which will reduce or eliminate common mode electromagnetic interference in telecommunications equipment.
There is also a need for such a modular jack which can reduce or eliminate crosstalk and common mode interference which is interchangeable with prior art modular jacks and which may be manufactured using conventional parts and tooling.